Wow. The Chandra X-ray Observatory just celebrated its 20th anniversary of being launched into space! It roared into orbit on board the Space Shuttle Columbia on July 23, 1999.
Continue reading “Watch the expansion of the Cas A supernova remnant with your own eyes!” »
Then again, maybe not.
In a previous post, I explained why quantum mechanics predicts that there are countless versions of you running around in what could be an infinite number of parallel universes.
This time, I’m going to introduce a controversial proposal by MIT physicist Max Tegmark, that uses these parallel universes to argue that you might actually be immortal.
I am going home :3.
Everybody wants a wormhole. I mean, who wants to bother traveling the long-and-slow routes throughout the universe, taking tens of thousands of years just to reach yet another boring star? Not when you can pop into the nearest wormhole opening, take a short stroll, and end up in some exotic far-flung corner of the universe.
There’s a small technical difficulty, though: Wormholes, which are bends in space-time so extreme that a shortcut tunnel forms, are catastrophically unstable. As in, as soon as you send a single photon down the hole, it collapses faster than the speed of light.
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Two researchers at Harvard University, Aavishkar A. Patel and Subir Sachdev, have recently presented a new theory of a Planckian metal that could shed light on previously unknown aspects of quantum physics. Their paper, published in Physical Review Letters, introduces a lattice model of fermions that describes a Planckian metal at low temperatures (Tà 0).
Metals contain numerous electrons, which carry electric current. When physicists consider the electrical resistance of metals, they generally perceive it as arising when the flow of current-carrying electrons is interrupted or degraded due to electrons scattering off impurities or off the crystal lattice in the metal.
“This picture, put forth by Drude in 1900, gives an equation for the electrical resistance in terms of how much time electrons spend moving freely between successive collisions,” Patel told Phys.org. “The length of this time interval between collisions, called the ‘relaxation time,’ or ‘electron liftetime,’ is typically long enough in most common metals for the electrons to be defined as distinct, mobile objects to a microscopic observer, and the Drude picture works remarkably well.”
Idk how I found this o.o
Last year we looked at multiverse theory and the highly speculative — but very real — science behind what has become a pop culture phenomenon. It isn’t just “Stranger Things” anymore. Interdimensional travel, and the portals that might allow it, are everywhere these days.
So, how to open a portal to another dimension?
Continue reading “Do Doors to Interdimensional Travel Exist?” »
One of the all-time great mysteries in physics is why our universe contains more matter than antimatter, which is the equivalent of matter but with the opposite charge. To tackle this question, our international team of researchers have managed to create a plasma of equal amounts of matter and antimatter – a condition we think made up the early universe.
Matter as we know it appears in four different states: solid, liquid, gas, and plasma, which is a really hot gas where the atoms have been stripped of their electrons. However, there is also a fifth, exotic state: a matter-antimatter plasma, in which there is complete symmetry between negative particles (electrons) and positive particles (positrons).
This peculiar state of matter is believed to be present in the atmosphere of extreme astrophysical objects, such as black holes and pulsars. It is also thought to have been the fundamental constituent of the universe in its infancy, in particular during the Leptonic era, starting approximately one second after the Big Bang.
By Rachel Courtland
The crust of neutron stars is 10 billion times stronger than steel, according to new simulations. That makes the surface of these ultra-dense stars tough enough to support long-lived bulges that could produce gravitational waves detectable by experiments on Earth.
Neutron stars are the cores left behind when relatively massive stars explode in supernovae. They are incredibly dense, packing about as much mass as the sun into a sphere just 20 kilometres or so across, and some rotate hundreds of times per second.
The Universe is expanding, and that expansion is speeding up over time. These two facts have been well established through observation, but we don’t know what’s causing that expansion. It seems to be some mysterious, unknown energy that acts like the opposite of gravity.
We call this hypothetical energy “dark energy”, and it’s been calculated to constitute around 72 percent of all the stuff that makes up the Universe. We don’t know what it actually is. But a new experiment has just allowed us to rule out one more thing that it isn’t: a new force.
“This experiment, connecting atomic physics and cosmology, has allowed us to rule out a wide class of models that have been proposed to explain the nature of dark energy, and will enable us to constrain many more dark energy models,’‘said physicist Ed Copeland of the University of Nottingham.
